阅读说明：本技术 一种山梨糖醇改性的磷酸盐粘结剂、其制备方法及使用方法 (Sorbitol modified phosphate binder, and preparation method and application method thereof ) 是由 夏露 高瑞 张友寿 任彦臻 于 2019-09-24 设计创作，主要内容包括：本发明属于铸造行业领域,具体涉及到一种山梨糖醇改性的磷酸盐粘结剂、其制备方法及使用方法,山梨糖醇改性的磷酸盐粘结剂按照重量百分比计包括：磷酸、氢氧化铝、硼酸、硅酸、氧化镁、氧化锌、氧化铜、纳米氧化钇、山梨糖醇、纯净水。本发明的山梨糖醇改性的磷酸盐粘结剂,相较于传统的磷酸盐粘结剂,它具有粘结强度更高,存放稳定性更好的优点；极少的加入量能够明显提高砂样的强度,在2.5％的磷酸盐粘结剂加入量下,砂样依然能够保持高强度。(The invention belongs to the field of foundry industry, and particularly relates to a sorbitol modified phosphate binder, a preparation method and a use method thereof, wherein the sorbitol modified phosphate binder comprises the following components in percentage by weight: phosphoric acid, aluminum hydroxide, boric acid, silicic acid, magnesium oxide, zinc oxide, copper oxide, nano yttrium oxide, sorbitol and purified water. Compared with the traditional phosphate binder, the sorbitol modified phosphate binder has the advantages of higher binding strength and better storage stability; the strength of the sand sample can be obviously improved by a small adding amount, and the sand sample can still maintain high strength under the adding amount of 2.5 percent of phosphate binder.)

1. A sorbitol modified phosphate binder characterized by: comprises the following components in percentage by weight: 50.148-51.682% of phosphoric acid, 11.499-11.850% of aluminum hydroxide, 1.780-1.835% of boric acid, 0.297-0.306% of silicic acid, 1.1187-1.223% of magnesium oxide, 0.890-0.917% of zinc oxide, 0.037-0.038% of copper oxide, 0.037-0.038% of nano yttrium oxide, 1.529-4.451% of sorbitol and 29.674-30.581% of purified water.

2. The sorbitol modified phosphate binder as claimed in claim 1, wherein: the phosphoric acid is industrial phosphoric acid with the mass fraction of 85%.

3. The sorbitol modified phosphate binder as claimed in claim 1, wherein: the aluminum hydroxide is aluminum hydroxide powder with the granularity of 300-340 meshes.

4. The sorbitol modified phosphate binder as claimed in claim 1, wherein: the zinc oxide is light zinc oxide, and the magnesium oxide is light magnesium oxide.

5. The sorbitol modified phosphate binder as claimed in claim 1, wherein: the sorbitol solution with the sorbitol concentration of 54.93 percent.

6. A process for the preparation of the sorbitol modified phosphate binder as claimed in any one of claims 1 to 5 comprising the steps of: (1) stirring and slowly heating phosphoric acid to 180-200 ℃;

(2) adding a small amount of aluminum hydroxide into the solution obtained in the step (1) for multiple times, and continuously stirring for reaction until the solution is transparent;

(3) adding one fourth of purified water, heating and stirring until the temperature of the solution is recovered to 180-200 ℃;

(4) sequentially adding boric acid and silicic acid, and continuously heating and stirring until the solution is transparent;

(5) adding one fourth of purified water, heating and stirring until the temperature of the solution is recovered to 180-200 ℃;

(6) sequentially adding a small amount of magnesium oxide and zinc oxide into the solution obtained in the step (5) for multiple times, and continuously heating and stirring until the solution is transparent;

(7) adding one fourth of purified water, heating and stirring until the temperature of the solution is recovered to 180-200 ℃;

(8) sequentially adding copper oxide and nano yttrium oxide powder into the solution obtained in the step (7), and continuously heating and stirring until the solution is transparent;

(9) adding sorbitol into the solution obtained in the step (8), and continuing heating and stirring until the solution is transparent;

(10) adding the balance of purified water, continuously heating and stirring until the solution is transparent and clear, and discharging to obtain the sorbitol modified phosphate binder.

7. A method of using the sorbitol modified phosphate binder as claimed in any one of claims 1 to 5 wherein: uniformly stirring quartz sand, a curing agent and a sorbitol modified phosphate binder accounting for 2.0-3.0% of the mass of the quartz sand, pouring into a mold, pounding tightly, blowing dry air in, and demolding.

8. The method of using a sorbitol modified phosphate binder as claimed in claim 7, wherein: the curing agent comprises 45.16-55.17% of silane coupling agent KH-550 and 44.83-54.84% of citric acid aqueous solution with mass concentration of 33.3%.

9. Method of use of the sorbitol modified phosphate binder as claimed in claim 8, wherein the specific steps of the method of use are: (1) mixing and stirring a citric acid aqueous solution which accounts for 0.75 percent of the mass of the quartz sand and a sorbitol modified phosphate binder uniformly at normal temperature for later use;

(2) uniformly mixing a silane coupling agent KH-550 accounting for 0.6 percent of the mass percent of the quartz sand with the quartz sand; then adding the mixture obtained in the step (1), and uniformly stirring;

(3) pouring the uniformly mixed sand material into a mould, pounding tightly, blowing dry air in, and demoulding.

Technical Field

The invention belongs to the field of casting industry, and particularly relates to a sorbitol modified phosphate binder, and a preparation method and a use method thereof.

Background

The phosphate binder serving as an environment-friendly casting inorganic binder has the characteristics of good collapsibility, no color and no smell, but has the characteristics of low tensile strength value, poor storage stability and the like compared with the traditional organic resin binder. Modification of phosphate binders to their relevant properties, such as the addition of some simple acid modifiers, improves their performance to some extent, but does not significantly improve their sand-like strength. In order to reduce the difference in strength from the conventional organic resin binder, more phosphate binder needs to be added. How to modify the phosphate binder and improve the strength of the phosphate binder to reduce the addition of the phosphate binder so as to meet the actual production requirement is a problem at present.

Disclosure of Invention

The invention aims to provide a sorbitol modified phosphate adhesive which has the advantages of higher adhesive strength and better storage stability.

The invention also aims to provide a preparation method of the sorbitol modified phosphate binder, which has simple and convenient preparation process and is easy to adjust.

The invention also aims to provide a use method of the sorbitol modified phosphate binder, which is simple and convenient to popularize.

The scheme adopted by the invention for realizing one of the purposes is as follows: a sorbitol modified phosphate binder comprising, in weight percent: 50.148-51.682% of phosphoric acid, 11.499-11.850% of aluminum hydroxide, 1.780-1.835% of boric acid, 0.297-0.306% of silicic acid, 1.1187-1.223% of magnesium oxide, 0.890-0.917% of zinc oxide, 0.037-0.038% of copper oxide, 0.037-0.038% of nano yttrium oxide, 1.529-4.451% of sorbitol and 29.674-30.581% of purified water.

The invention adopts sorbitol modified phosphate binder, and the molecular formula of sorbitol is C₆H₁₄O₆And the molecular weight is 182.17. The sorbitol aqueous solution is viscous transparent liquid, has optical activity, slight sweet taste, hygroscopicity, and instability at high temperature, and can dissolve various metals. Can participate in anhydrization, esterification, etherification, oxidation, reduction, isomerization and other reactions, and can form a complex with various metals.

Preferably, the phosphoric acid is 85% by mass of industrial phosphoric acid.

Preferably, the aluminum hydroxide is aluminum hydroxide powder with the particle size of 300-340 meshes.

Preferably, the zinc oxide is light zinc oxide, and the magnesium oxide is light magnesium oxide.

Preferably, the sorbitol solution has a sorbitol concentration of 54.93%.

The second scheme adopted by the invention for achieving the purpose is as follows: a preparation method of the sorbitol modified phosphate binder comprises the following steps: (1) stirring and slowly heating phosphoric acid to 180-200 ℃;

(2) adding a small amount of aluminum hydroxide into the solution obtained in the step (1) for multiple times, and continuously stirring for reaction until the solution is transparent;

(3) adding one fourth of purified water, heating and stirring until the temperature of the solution is recovered to 180-200 ℃;

(4) sequentially adding boric acid and silicic acid, and continuously heating and stirring until the solution is transparent;

(5) adding one fourth of purified water, heating and stirring until the temperature of the solution is recovered to 180-200 ℃;

(6) sequentially adding a small amount of magnesium oxide and zinc oxide into the solution obtained in the step (5) for multiple times, and continuously heating and stirring until the solution is transparent;

(7) adding one fourth of purified water, heating and stirring until the temperature of the solution is recovered to 180-200 ℃;

(8) sequentially adding copper oxide and nano yttrium oxide powder into the solution obtained in the step (7), and continuously heating and stirring until the solution is transparent;

(9) adding sorbitol into the solution obtained in the step (8), and continuing heating and stirring until the solution is transparent;

(10) adding the balance of purified water, continuously heating and stirring until the solution is transparent and clear, and discharging to obtain the sorbitol modified phosphate binder.

The scheme adopted by the invention for realizing the third purpose is as follows: the application method of the sorbitol modified phosphate binder comprises the steps of uniformly stirring quartz sand, a curing agent and the sorbitol modified phosphate binder accounting for 2.0-3.0% of the mass of the quartz sand, pouring the mixture into a mold, pounding the mold tightly, blowing dry air in the mold, and demolding.

Preferably, the curing agent comprises 45.16-55.17% of silane coupling agent KH-550 and 44.83-54.84% of citric acid aqueous solution with mass concentration of 33.3%.

Preferably, the using method comprises the following specific steps: (1) mixing and stirring a citric acid aqueous solution which accounts for 0.75 percent of the mass of the quartz sand and a sorbitol modified phosphate binder uniformly at normal temperature for later use;

(2) uniformly mixing a silane coupling agent KH-550 accounting for 0.6 percent of the mass percent of the quartz sand with the quartz sand; then adding the mixture obtained in the step (1), and uniformly stirring;

(3) pouring the uniformly mixed sand material into a mould, pounding tightly, blowing dry air in, and demoulding.

The invention has the following advantages and beneficial effects: compared with the traditional phosphate binder, the sorbitol modified phosphate binder has the advantages of higher binding strength and better storage stability; the strength of the sand sample can be obviously improved by a small adding amount, and the sand sample can still maintain high strength under the adding amount of 2.5 percent of phosphate binder.

Aiming at the current situations that the sand core strength is low and the storage is unstable in the application process of the existing phosphate inorganic binder, the sorbitol modified phosphate binder assists demoulding and hardening in a compressed air mode, and compared with the traditional phosphate binder, the sorbitol modified phosphate binder has the advantages that: high strength, good storage stability, green protection, no pollution, short demoulding time and complete implementation possibility.

The sorbitol modified phosphate binder is green, nontoxic and pollution-free, can be used for hardening and demoulding sand molds (cores) quickly by being assisted with compressed air, has high strength, has wide application prospect, and has remarkable economic and social benefits.

The preparation method has simple process, and the product has wide application prospect and remarkable economic and social benefits.

The sand sample prepared by the binder has no unpleasant odor from sand mixing, molding, core making and pouring in the whole casting process and production process, is nontoxic and tasteless, is environment-friendly, has low cost, and basically has no special requirements on the existing casting equipment.

Detailed Description

The following examples are provided to further illustrate the present invention for better understanding, but the present invention is not limited to the following examples.

The effects of sorbitol and dry compressed air were demonstrated by comparing the immediate strength of the sand hardening after sample preparation, the strength of 24h, 48h, 72h, 96h using the method of comparative example, with no sorbitol and with sorbitol as the phosphate binder, and with normal compressed air and dry compressed air as the method of use.

The sorbitol modified phosphate binder of the present invention comprises the following components: 85% industrial phosphoric acid, 320-mesh aluminum hydroxide powder, boric acid (analytically pure), silicic acid (analytically pure), light magnesium oxide (analytically pure), light zinc oxide (analytically pure), copper oxide, nano yttrium oxide, sorbitol solution with the concentration of 54.93% and purified water.

In the following examples and comparative examples, the curing agent used comprised two components, one silane coupling agent KH-550, accounting for 0.6% by mass of the silica sand, and two citric acid aqueous solutions (concentration 33.3% by mass) accounting for 0.75% by mass of the silica sand. The specific using steps are as follows: (1) mixing and stirring a citric acid aqueous solution accounting for 0.75 percent of the mass of the quartz sand and a phosphate binder (including a sorbitol modified phosphate binder and an unmodified phosphate binder) uniformly at normal temperature for later use;

(2) uniformly mixing a silane coupling agent KH-550 accounting for 0.6 percent of the mass percent of the quartz sand with the quartz sand; then adding the mixture obtained in the step (1), and uniformly stirring;

(3) and pouring the uniformly mixed sand material into an 8-shaped sample mold for subsequent operation.

Comparative example 1:

the proportion of the sorbitol phosphate binder is not added: 338g of 85% industrial phosphoric acid, 77.5g of 320-mesh aluminum hydroxide powder, 12g of boric acid, 2g of silicic acid, 8g of light magnesium oxide, 6g of light zinc oxide, 0.25g of copper oxide, 0.25g of nano yttrium oxide and 200g of purified water; the preparation method comprises the following steps:

1) adding phosphoric acid into a reaction kettle, starting a stirrer and a heater, and slowly heating to 180-200 ℃;

2) adding a small amount of aluminum hydroxide powder into the reaction kettle for multiple times, and continuously stirring for reaction until the solution in the reaction kettle is transparent;

3) adding 50g of purified water, heating and stirring until the temperature of the solution is recovered to the temperature before adding water;

4) sequentially adding boric acid and silicic acid powder, and continuously heating and stirring until the solution is transparent;

5) adding 50g of purified water, heating and stirring until the temperature of the solution is recovered to the temperature before adding water;

6) sequentially adding a small amount of light magnesium oxide and zinc oxide powder into the reaction kettle for multiple times, and continuously heating and stirring until the solution is transparent;

7) adding 50g of purified water, heating and stirring until the temperature of the solution is recovered to the temperature before adding water;

8) sequentially adding copper oxide and yttrium oxide powder into a reaction kettle, and continuously heating and stirring until the solution is transparent;

9) adding the last 50g of purified water, continuously heating and stirring until the solution is transparent and clear, and discharging.

The using method comprises the following steps:

1500g of quartz sand, curing agent and 37.5g of phosphate binder are uniformly stirred, then poured into an 8-shaped sample mold, pounding is carried out, compressed air without dehumidification treatment is blown in for 5 minutes, demolding is carried out, and the tensile strength is tested.